1. Field of the Invention
This invention relates to a transmission apparatus, a recording apparatus, a transmission and reception apparatus, a transmission method, a recording method and a transmission and reception method by which data are transmitted and received through a data interface in accordance with a predetermined data communication format.
2. Description of the Related Art
As a recording apparatus and/or a reproduction apparatus which can record and/or reproduce music and so forth, a recording apparatus and/or a reproduction apparatus are known on which a magneto-optical disc, a magnetic tape or the like on which an audio signal is recorded as a digital signal is used as a recording medium. A mini disc (Trade Mark) is known as such a magneto-optical disc as mentioned above. In a recording and reproduction system in which the magneto-optical disc is used, a user can not only record and reproduce an audio signal of tunes and so forth as programs, but also record a title unique to the recording medium, that is, a disc name, and titles, that is, track names, of the programs such as tunes recorded on the recording medium as character information on the recording medium. For example, upon reproduction, the disc title, the titles of the tunes, the names of artists and so forth can be displayed on a display section of a reproduction apparatus.
It is to be noted that, in the present specification, the term xe2x80x9cprogramxe2x80x9d is used to signify a unit of audio data or the like such as a tune as main data recorded on a disc. For Example, audio data for one tune make one program. Also the term xe2x80x9ctrackxe2x80x9d is used in the same significance as the xe2x80x9cprogramxe2x80x9d.
A mini disc system in which a mini disc is used as a recording medium has been proposed by the Assignee of the present invention wherein a recording area. into which sub data incidental to audio data as main data can be recorded is provided separately from a recording area into which the main data are recorded on a mini disc such that still picture data and character data can be recorded as the sub data. It is to be noted that the character data in the present specification include also data of symbols, marks and so forth.
For example, also a conventional mini disc system different from the mini disc system described above can record character information such as a disc name and a track name. Such character information is recorded in a corresponding relationship to each program in the U-TOC (User Table Of Contents) of a mini disc. However, since the U-TOC itself does not have a very large capacity, it merely allows recording of characters of titles and so forth as described above.
In contrast, where an area exclusively used to record sub data therein is provided on a mini disc, it can be realized readily to record not only character information but also video data which do not require a very large capacity such as, for example, a still picture.
In recent years, digital direct broadcasting has spread progressively. The digital direct broadcasting is tough against noise and fading, for example, when compared with existing analog broadcasting, and allows transmission of a signal of a high quality. Further, the digital direct broadcasting exhibits an augmented frequency utilization efficiency and allows utilization of multiple channels. In particular, the digital direct broadcasting allows assurance of several hundreds channels with one satellite. In such digital direct broadcasting, a large number of exclusive channels for sports, motion pictures, music, news and so forth are prepared, and programs for respectively exclusive contents are broadcast in the exclusive channels.
It has been proposed to make use of such a digital direct broadcasting system as described above so that a user can download audio data of a tune or the like or can, for example, make a purchase contract regarding some commodity while observing a broadcasting screen. In short, the digital direct broadcasting system involves data service broadcasting together with broadcasting of ordinary broadcasting contents.
As an example, in downloading of music data, the broadcasting side multiplexes tune data and video data of an album jacket or the like and text data of liner notes, that is, sentences regarding tunes, artists and so forth, incidental to the tune data and broadcasts the multiplexed data in parallel to a broadcasting program. Upon downloading of such tune data and incidental information, a GUI (Graphical User Interface) screen, which is an operation screen for downloading, is displayed so that a user can perform interactive operations. Also data for such GUI screen outputting are broadcast in a multiplexed condition.
On the user side who owns a reception apparatus, while a desired channel is selected, a predetermined operation is performed for the reception apparatus so that a GUI screen for downloading tune data is displayed or outputted. Then, the user performs an operation for the operation screen displayed in this manner so that, for example, the data are supplied to and recorded by a digital audio apparatus connected to the reception apparatus.
Further, in recent years, a data transmission system has been proposed wherein various electronic apparatus such as digital AV (Audio Visual) apparatus and a personal computer apparatus are connected to each other, for example, by an IEEE (Institute of Electrical Engineers) 1394 bus so that data may be communicated between them.
From the technical background described above, it is a possible idea to provide a system wherein audio data as main data and video data and text data as sub data incidental to the audio data which can be handled by the mini disc system described above are broadcast as download data, for example, by digital direct broadcasting such that the user side can receive the download data by means of a digital direct broadcasting reception apparatus and record the received download data onto a mini disc by means of a mini disc player over an IEEE 1394 bus.
Further, if a personal computer apparatus or some other AV apparatus is connected to a mini disc player of such a system as just described over an IEEE 1394 bus, then also it is possible, for example, to fetch data reproduced by the AV apparatus into the personal computer apparatus and perform editing processing and so forth for the data using the personal computer or to cause the personal computer to perform operation control for some other AV apparatus.
Where the AV system whose components are connected to each other by the IEEE 1394 bus as described above transmits audio data as main data and video data or text data as sub data which are handled by the mini disc system described above, it is preferable to establish a transmission form which exhibits an efficiency as high as possible taking, for example, a burden to hardware, software and so forth into consideration while the IEEE 1394 standard is observed.
It is an object of the present invention to provide a transmission apparatus, a recording apparatus, a transmission and reception apparatus, a transmission method, a recording method and a transmission and reception method by which data can be communicated between different apparatus over a single data bus in accordance with a first communication method wherein data can be transmitted and/or received periodically and a second communication method wherein data can be transmitted and/or received asynchronously.
In order to attain the object described above, according to a first aspect of the present invention, there is provided an information transmission apparatus which can communicate data with another apparatus over a single data bus in accordance with a first communication system wherein data can be transmitted periodically and a second communication system wherein data can be transmitted asynchronously, including discrimination means for discriminating whether data to be transmitted are main data to be outputted successively in time or sub data relating to the main data and transmission means for transmitting, when the discrimination means discriminates that the data to be transmitted are main data to be outputted successively in time, the data in accordance with the first communication system but transmitting, when the discrimination means discriminates that the data are sub data relating to the main data, the data in accordance with the second communication system.
According to a second aspect of the present invention, there is provided a recording apparatus which communicates data over a single data bus in accordance with a first communication system wherein data can be received periodically and a second communication system wherein data can be received asynchronously and records the received data onto a recording medium, including discrimination means for discriminating whether data received are main data transmitted thereto in accordance with the first communication system and to be outputted successively in time or sub data transmitted in accordance with the second communication system and relating to the main data and recording means for recording, when the discrimination means discriminates that the received data are main data to be outputted successively in time, the received main data into a first area of the recording medium but recording, when the discrimination means discriminates that the received data are sub data relating to the main data, the received sub data into a second area of the recording medium.
According to a third aspect of the present invention, there is provided a transmission and reception system, including first reception means for receiving main data to be outputted successively in time and sub data relating to the main data, transmission means for transmitting the main data received by the first reception means and to be outputted successively in time in accordance with a first communication system wherein data can be transmitted periodically and transmitting the sub data relating to the main data in accordance with a second communication system wherein data can be transmitted asynchronously, second reception means for receiving the main data and the sub data transmitted from the transmission means over a single cable, and separation means for separating the main data transmitted in accordance with the first communication system and received by the second reception means and the sub data transmitted in accordance with the second communication system and received by the second reception means from each other.
According to a fourth aspect of the present invention, there is provided an information transmission method by which data can be communicated between different apparatus over a single data bus in accordance with a first communication system wherein data can be transmitted periodically and a second communication system wherein data can be transmitted asynchronously, including the steps of discriminating whether data to be transmitted are main data to be outputted successively in time or sub data relating to the main data, and transmitting, when it is discriminated by the discriminating step that the data to be transmitted are main data to be outputted successively in time, the data in accordance with the first communication system but transmitting, when it is discriminated by the discriminating step that the data are sub data relating to the main data, the data in accordance with the second communication system.
According to a fifth aspect of the present invention, there is provided a recording method by which data are communicated over a single data bus in accordance with a first communication system wherein data can be received periodically and a second communication system wherein data can be received asynchronously and the received data are recorded onto a recording medium, including the steps of discriminating whether data received are main data transmitted thereto in accordance with the first communication system and to be outputted successively in time or sub data transmitted in accordance with the second communication system and relating to the main data, and recording, when it is discriminated by the discriminating step that the received data are main data to be outputted successively in time, the received main data into a first area of the recording medium but recording, when it is discriminated by the discriminating step that the received data are sub data relating to the main data, the received sub data into a second area of the recording medium.
According to a sixth aspect of the present invention, there is provided a transmission and reception method, including a first receiving step of receiving main data to be outputted successively in time and sub data relating to the main data, a transmitting step of transmitting the received main data to be outputted successively in time in accordance with a first communication system wherein data can be transmitted periodically and transmitting the sub data relating to the main data in accordance with a second communication system wherein data can be transmitted asynchronously, a second receiving step of receiving the main data and the sub data transmitted in the transmitting step over a single cable, and a separating step of separating the received main data transmitted in accordance with the first communication system and the received sub data transmitted in accordance with the second communication system from each other.
The above and other objects, features and advantages of the present invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings in which like parts or elements denoted by like reference symbols.